When forming the ing form of a verb in spanish you add what to stem instead ing?

You don't add "ing" to form the continuous tense in Spanish. Spanish uses a different structure for the present continuous tense, which is formed with "estar" + the present participle.

Here's how it works:

* Estar: This verb means "to be" and is used to indicate a state of being.

* Present participle: This is formed by adding -ando or -iendo to the stem of the verb.

Examples:

* Hablar (to speak) → Hablando (speaking)

* Comer (to eat) → Comiendo (eating)

* Caminar (to walk) → Caminando (walking)

Important: The ending "-ando" is used for verbs that end in -ar in the infinitive, and "-iendo" is used for verbs that end in -er and -ir in the infinitive.

So instead of adding "ing," you need to add -ando or -iendo to the stem of the verb and combine it with estar to form the present continuous tense in Spanish.